JPH0611564Y2 - Case waterproof structure - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a waterproof structure of a case for improving the waterproof performance between a grommet fitted to the case and the case.

[Conventional technology]

As shown in FIGS. 3 and 4, the waterproof structure of the fitting portion between the grommet that seals the gap between the wire that is routed through the case and the case and supports the wire so as not to damage it, and the fitting part is as shown in FIGS. Has become.

In the figure, the case 1 has a joint surface 3 on the upper end surface for overlapping the lid 2 and a grommet fitting portion 4 opening to the joint surface 3.

The grommet fitting portion 4 is formed in a U shape by a semicircular curved surface and a plane connecting the curved surface to the joint surface 3, and a protrusion 5 is provided on the inner peripheral surface 4a of the U shape along the circumferential direction. .

On the other hand, the grommet 6 is made of a rubber-like elastic material, is composed of a tube 7, a bellows portion 8 and a thick wall portion 9, and has an electric wire insertion hole 10 formed therein.

A groove 11 that fits into the protrusion 5 is formed in the thick peripheral wall portion 9 that is press-fitted into the grommet fitting portion 4 of the case 1.

The grommet 6 configured as described above has the wire insertion hole 10
After the electric wire w is inserted inside the tube and the tube 7 is tape-wound with the electric wire w, the thick peripheral wall portion 9 is press-fitted into the grommet fitting portion 4, and the projection 5 is fitted into the groove 11.

Next, the lid 2 is placed on the joint surface 3 of the case 1 and fastened to the joint surface 3 by a known fastening means.

At this time, the lid 3 presses the upper end surface of the thick-walled peripheral wall portion 9 to bring it into close contact.

Thus, the electric wire w and the case 1 are waterproof and sealed by the grommet 6.

[Problems to be solved by the invention]

When a relay block storage case with the above waterproof structure is installed in the engine room of a car, water with a low water pressure such as rainwater that enters while the car is running is blocked by the case's waterproof structure. Although water does not enter inside the case, when pressure water like high pressure car wash water is poured into the case, the grommet that receives the pressure water elastically deforms and presses against the case with elastic force. The pressing force of the grommet, which was generated, decreased, and the pressured water sometimes intruded into the case.

If water enters the case, an accident such as a leak current may occur in electric parts inside the case.

The present invention has been made to solve such a problem.

[Means for solving problems]

The present invention provides a waterproof structure in which pressure water is not applied around the case fitting surface of the grommet, and a waterproof wall is erected on the inner peripheral surface of the grommet fitting part along the outer edge of the case.
A groove is provided inside the case of the waterproof wall, a drainage hole penetrating the outside of the case is provided below the groove, and a protrusion is formed inside the case of the groove along the circumferential direction of the inner peripheral surface. To provide.

Further, the thick peripheral wall portion of the grommet fitted to the inner peripheral surface is provided with a flange portion which is in close contact with the waterproof wall and fits into the concave groove, and a groove which fits into the protrusion.

[Action]

With the above configuration, when pressure water such as water for high-pressure car wash is poured into the case, the area around the case fitting surface of the grommet is covered with the waterproof wall and does not directly receive the pressure water.

Therefore, the pressing force against the case is maintained without being affected by the pressurized water around the grommet fitting surface.

The part of the grommet that is not covered by the waterproof wall is deformed by receiving pressured water, creating a gap between the tip of the waterproof wall and the grommet, and it is conceivable that the groove will leak from this gap, but the leaked water is already The pressure is lost and there is no force to lift the case fitting part of the grommet, and it is discharged to the outside of the case through the drainage hole of the concave groove.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

The same parts as those in the conventional example are designated by the same reference numerals.

In FIG. 1, a case 1 has a joint surface 3 to which a lid 2 is attached on an upper end surface thereof, a grommet fitting portion 4 opening to the joint surface, and an inner peripheral surface 4 a of the grommet fitting portion 4 in a circumferential direction. The protrusion 5 is provided along the same as in the conventional example.

In addition, the thick peripheral wall portion 9 of the grommet 6 is provided with the groove 11 that fits into the protrusion 5, as in the conventional example.

The protrusion 5 and the groove 11 are fitted to each other by the case 1 and the grommet 6.
It is needless to say that the waterproof effect can be enhanced even if the grommet 6 is provided with a protrusion and the case 1 is provided with a groove.

Further, in the present invention, the waterproof wall 12 is erected along the edge of the inner peripheral surface 4a in the case outer direction, and the groove 13 is provided in the case inner direction of the waterproof wall 12, and is located below the groove 13. A drainage hole 14 is provided so as to penetrate to the outside of the case 1.

On the other hand, the grommet is in close contact with the waterproof wall 12 and has the groove 13
A flange 15 is provided to be fitted into.

The operation of the waterproof structure of the case configured as described above will be described.

When the electric wire w is inserted into the electric wire insertion hole 10 inside the grommet 6 and the tube 7 is tape-wound with the electric wire w, the thick peripheral wall portion 9 is press-fitted into the grommet fitting portion 4,
The flange portion 15 is fitted in the concave groove 13 in a state of being in close contact with the waterproof wall 12, and the projection 5 is fitted in the groove 11.

Next, the lid 2 is fastened to the joint surface 3, and the lid 2 is attached to the thick wall 9
Press to adhere.

When pressure water such as high-pressure car wash water is poured into the case assembled as described above, since the area around the case fitting surface of the grommet is covered with the waterproof wall 12, the pressure water is not directly received. , The grommet 6 is kept in pressure contact with the case 1.

However, the thick peripheral wall portion 9 not covered by the waterproof wall 12
Is elastically deformed by the pressure of the pressure water, and a gap is created between the tip portion of the waterproof wall 12 and the thick peripheral wall portion 9. Even if water leaks from this gap, the concave groove 13 and the flange portion 15 are Since the water is in intimate contact, the water entering is decompressed, and there is no force to push up the thick peripheral wall portion 9 that adheres to the inner peripheral surface 4a to enter the inner peripheral surface 4a. After that, it is discharged to the outside of the case 1.

Thus, the case 1 is also waterproof against pressure water.

〔effect〕

The waterproof structure of the conventional case cannot completely block the intrusion of water by the pressure water, but the waterproof structure of the present invention can completely prevent the intrusion of water.

[Brief description of drawings]

FIGS. 1 and 2 show an embodiment of the present invention, FIG. 1 is a perspective view of a grommet and a case main part, FIG. 2 is a longitudinal sectional view of a grommet assembled case main part, and FIG. FIG. 4 is a perspective view of a grommet and a main part of the case in the conventional example, and FIG. 4 is a vertical cross-sectional view of the main part of the case in which the grommet in the conventional example is assembled. 1 ... Case, 2 ... Lid, 3 ... Joining surface, 4 ... Grommet fitting part, 4a ... Inner peripheral surface, 5 ... Protrusion, 6 ... Grommet, 9 ... Thick wall part, 11 ...... Groove, 12 ...... Waterproof wall, 13 ...... Concave groove, 14 ...... Drainage hole, 15 ...... Brim part.

Claims (1)

[Scope of utility model registration request] 1. A waterproof wall is provided upright along an outer edge of an inner peripheral surface of a grommet fitting portion provided in a case, a groove is provided inside the case of the waterproof wall, and a position below the groove is provided. A drainage hole penetrating to the outside of the case, a protrusion is provided inside the case of the groove along the circumferential direction of the inner peripheral surface, and a thick peripheral wall of a grommet fitted to the inner peripheral surface. A waterproof structure for a case, characterized in that a flange portion which is in close contact with the waterproof wall and is fitted into the concave groove and a groove which is fitted into the upper projection are provided in the portion.